Embodiments of the inventive concepts relate to three-dimensional (3D) semiconductor memory devices and, more particularly, to 3D semiconductor memory devices with improved reliability and/or integration density.
Semiconductor devices have been more highly integrated to provide improved performance and/or lower manufacture costs. The integration density of semiconductor devices directly affects the costs of the semiconductor devices, thereby resulting in a demand of highly integrated semiconductor devices. The integration density of two-dimensional (2D) or planar semiconductor devices may be mainly determined by the area a unit memory cell occupies. Therefore, the integration density of the 2D or planar semiconductor devices may be greatly affected by a technique of forming fine patterns. However, since high-priced apparatuses are needed to form fine patterns, the integration density of 2D semiconductor devices continues to increase but is still limited. Thus, three-dimensional (3D) semiconductor memory devices have been developed to overcome the above limitations. 3D semiconductor memory devices may include memory cells three-dimensionally arranged.